The invention relates to a fixture for an electronic flash, and more particularly, to such fixture including a connection terminal utilized for synchronized flashlight illumination and another connection terminal which is used to transmit an electrical signal indicative of the completion of a charging operation or the completion of a flashlight illumination of an electronic flash to a camera on which it is mounted, and enabling an electronic flash to be detachably mounted on a hot shoe of the camera. Such an electronic flash will be referred to hereafter as "of the kind specified."
A conventional fixture for an electronic flash is illustrated in FIGS. 1 and 2. Referring to these Figures, there is shown electronic flash 1 having fixture 2 which is provided on the bottom surface thereof. Fixture 2 has connection member 3 in the form of a square plate which is adapted to be fitted into guide groove 8 formed in hot shoe 7 (see FIG. 2) that is provided on the top surface of a camera. Subsequently, fixing knob 4 may be turned to secure connection member 3 to shoe 7, thus mounting electronic flash 1 on the camera. It will be seen that a plurality of connection terminals are provided on bottom surface 3a of connection member 3, including centrally located terminal 5 which is used to permit a synchronized flashlight illumination, and connection terminals 6a, 6b located on the opposite sides thereof and which are used to transmit an electrical signal to the camera which is indicative of the completion of a charging operation or the completion of a flashlight illumination of the electronic flash. These terminals are provided in the form of retractable dowels.
Hot shoe 7 includes an inner bottom surface 7a which is adapted to be engaged by bottom surface 3a of connection member 3. Three connection terminals 10, 11a, 11b are disposed in a layout corresponding to terminals 5, 6a, 6b. It is to be understood that terminals 10, 11a, 11b are electrically insulated from each other by forming part of bottom wall of hot shoe 7 with insulating member 9, and remain exposed. As indicated by an arrow a, connection member 3 of the electronic flash is inserted into guide groove 8 from the rear side.
FIG. 3 shows hot shoe 12 of a more usual camera which has single connection terminal 14 alone that is used for providing a synchronized flashlight illumination. Only region 13 of the bottom surface of hot shoe 12 is electrically insulated by an insulating member while the remainder is formed by an electrically conductive member such as metal, so that when electronic flash 1 having fixture 2 is mounted on such hot shoe 12, the conductive material of the bottom surface of shoe 12 will short-circuit connection terminals 6a, 6b, causing a malfunctioning or possibly destroying the function of electronic flash 1. It will be understood that the same difficulty occurs also when electronic flash 1 is mounted on a usual accessory shoe which has no synchronized flashlight terminal.